What does base excess mean on blood gas?

What does base excess mean on blood gas?

What does base excess mean on blood gas?

The base excess It is defined as the amount of acid required to restore a litre of blood to its normal pH at a PaCO2 of 40 mmHg. The base excess increases in metabolic alkalosis and decreases (or becomes more negative) in metabolic acidosis, but its utility in interpreting blood gas results is controversial.

How do you calculate ABG base excess?

Most equations used for calculation of the base excess (BE, mmol/l) in human blood are based on the fundamental equation derived by Siggaard-Andersen and called the Van Slyke equation: BE = Z x [[cHCO3-(P) – C7. 4 HCO3-(P)] + beta x (pH -7.4)].

How do you calculate compensation for respiratory acidosis?

III. Calculation: Calculated PaCO2 in Metabolic Conditions

  1. Metabolic Acidosis with expected compensation. PaCO2 = 1.5 x HCO3 + 8 (+/- 2) PaCO2Delta = 1.2 x BicarbDelta. PaCO2 will not typically drop below 10 mmHg in respiratory compensation.
  2. Metabolic Alkalosis with expected compensation. PaCO2 = 0.7 x HCO3 + 20 (+/- 1.5)

How do you calculate blood gases?

ABG Components:

  1. pH = measured acid-base balance of the blood.
  2. PaO2 = measured the partial pressure of oxygen in arterial blood.
  3. PaCO2 = measured the partial pressure of carbon dioxide in arterial blood.
  4. HCO3 = calculated concentration of bicarbonate in arterial blood.

What does high base excess indicate?

A high base excess, thus metabolic alkalosis, usually involves an excess of bicarbonate. It can be caused by. Compensation for primary respiratory acidosis. Excessive loss of HCl in gastric acid by vomiting. Renal overproduction of bicarbonate, in either contraction alkalosis or Cushing’s disease.

What does a high base excess mean?

A high base excess (> +2mmol/L) indicates that there is a higher than normal amount of HCO3– in the blood, which may be due to a primary metabolic alkalosis or a compensated respiratory acidosis.

How do you fix base excess?


  1. Base excess = 0.9287 [HCO3 − 24.4 + 14.83 (pH − 7.4)]
  2. Base excess = 0.02786 × Pco2 × 10(pH −6.1) + 13.77 × pH − 124.58.
  3. Base required = (Base excess × −1) × (Weight in kg) × 0.4.
  4. Base excess correction = 0.25 (4.2 − Serum albumin in g/dL)

What does a negative base excess indicate?

Together with the bicarbonate, the base excess gives you an indication of the metabolic component of the blood gas results. A positive base excess means excess base, i.e. a metabolic alkalosis, whereas a negative base excess means reduced base, i.e. a metabolic acidosis.

How are arterial blood gases ( ABG ) calculated?

Arterial Blood Gases (ABG) Calculator The arterial blood gases calculator calculates whether an individual is in metabolic acidosis, metabolic alkalosis, respiratory acidosis, respiratory alkalosis, or is normal. The calculator also determines whether the state is compensated or uncompensated.

What does SID mean in a blood gas calculator?

SID means Strong Ion Difference (SIDa and SIDe for SID apparent or effective). SIG is the Strong Ion Gap. BE is the Base excess (SBE for Standar Base Excess). Stewart’s calculations give an estimation of the individual effects of various parameter variation (Sodium concentration, Chloride, Albumine.) on the base excess.

What is the normal pH of arterial blood gas?

Normal Arterial Blood Gas Values pH : 7.36-7.44 PaCO2 : 36-44 mm Hg HCO3 : 22-26 mEq/L

How to use blood gas calculator in intensive care?

To be used for the evaluation of the quality of the compensatory response of the patient. A more detailed information might be implemented in the future version of the software. – Step 1: enter the required values, obtained from blood gaz machine and lab results. – Step 2: click “Calculate” button.